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    <title>Document</title>
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    <script>
        "use strict";
        const tom = 123;
        const TOM_BIRTHDAY = '1999.1.1';
        // TOM_BIRTHDAY = '1999.1.6';
        alert(TOM_BIRTHDAY);
    </script>
30课 JavaScript基础入门总结

    演示首页 郭孟涛 QQ250285636
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